Darling River awash in more fish carcasses

Hundreds of thousands of fish carcasses have been found floating in the Darling River in a second wave of mass deaths in a month.

Another batch of fish carcasses was found floating in the weir pool at Menindee, in far-western NSW, yesterday by Graeme McCrabb. Picture: AAP/Graeme McCrabb

Hundreds of thousands of fish carcasses have been found floating in the Darling River less than a month after a mass death of about one million fish in the same area.

Graeme McCrabb, who lives in Menindee in far-western NSW, found the fish and took to social media to express his concern. “It’s starting again,” he wrote on Facebook.

The NSW Department of Primary Industries has sent officers to investigate the deaths of “large numbers of bony bream and smaller numbers of other ­species” at Menindee Weir Pool, southeast of Broken Hill.

Another Menindee resident, Rob Gregory, said there were as many as 300 dead bony bream and other native species.

“There are lots of yabbies crawling up the bank … they must be suffocating,” Mr Greg­ory said.

“Fisheries officers found hundreds of thousands of fish have died including bony herring, perch and carp, following initial reports of tens of thousands of fish,” a DPI statement said.

“The fish deaths are the result of critically low levels of dissolved oxygen likely linked to the mixing of weir pool water following the significant drop in temperatures over the last ­couple of days.”

The DPI warned that the very low flow of water across the NSW waterways and soaring heatwave temperatures meant fish in the area remained at “high risk” of further kills.

An interim report into fish deaths in the Darling River found sky-high temperatures followed by sudden cooler temperatures and rainfall killed off algae in the water, and dissolved oxygen dropped below critical levels. The deaths at the beginning of this month occurred when temperatures fell from 46C to 28C in a two-day period.

Central Darling Shire Council has deployed a clean-up operator who will also be recording information about the deaths.

Additional reporting: AAP